摘要
随着航天技术的不断发展,航天器的数量日益增多,迫切需要一种统一的、高性能的天基授时手段,以便为各类航天器的高效协同提供保障.导航星间链路广泛适用于卫星精密定轨与时间同步,并且覆盖了星座内的中高轨卫星,因此可作为一种理想的天基高精度时间传递手段.现有的导航星间链路时间同步方法依赖于导航卫星具备星历信息,并不适用于位置精度较低且空间信息缺乏完整性的任意空间飞行器.本文在导航星间链路双向测量原理的基础上,提出了一种动态条件下时延修正方法,该方法计算简单、工程可实现性强,只需要空间飞行器终端具备多普勒测量或连续伪距测量功能,即可实现空间飞行器在一般位置精度条件下的高性能时间同步.理论分析表明,授时精度优于0.1ns.最后,以地面站模拟空间飞行器,结合北斗星间链路星地实测数据开展了时间同步试验,试验结果验证了本方法的有效性.
With the development of space technology with increasing number of spacecraft and its expanding orbit, a uniform and high performance timing method is urgently required to guarantee the efficient cooperation among spacecrafts. Inter-satellite link （ISL） of navigation constellation is widely used for precise orbit determination and time synchronization. Because the coverage of ISL extends to medium Earth orbits （MEO） and high Earth orbits （HEO） users, it can be used as an ideal space-based high-precision time transfer method. Highly depending on ephemeris parameters, current ISL based time synchronization method is inappliable to spacecraft with low-precision and incomplete space position information. A new dynamic delay correction method is proposed on the basis of dual-way ranging. Assume the Doppler or pseudo-range can be measured by the ISL terminal in users, the method can achieve high-precision time synchronization with middle-precision position information which is easily calculated and realized. Theoretic analysis shows that the timing accuracy is prior to 0.1 ns. Finally, experiments on time synchronization between BeiDou satellite and ground station which is used to simulate a spacecraft are conducted. The test results verify the validity of the method.
作者
郭熙业
周永彬
杨俊
GUO XiYe ZHOU YongBin YANG Jun(College of Mechatronics Engineering and Automation, National University of Defense Technology, Changsha 410073, China)
出处
《中国科学：技术科学》
EI
CSCD
北大核心
2017年第1期71-79,共9页
Scientia Sinica(Technologica)
关键词
星间链路
时间传递
空间飞行器
双向测量
动态时延修正
inter-satellite link, time transfer, spacecraft, dual-way ranging, dynamic delay correction
